A. Field of the Invention
This invention generally relates to the field of Analog Display Services Interface (ADSI) and in particular to a system and method for interfacing a screen-display telephone device with the World Wide Web or Internet.
B. Description of the Prior Art
1. ADSI Display Devices
ADSI is a telecommunications protocol standard developed by Bellcore and published in Bell Communications Research report "Generic Requirements for an SPCS to Customer Premises Equipment Data Interface for Analog Display Services," Technical Reference TR-NWT-001273, December 1992 (incorporated herein by reference). ADSI enables alternate voice and data capability over the existing analog telephone network. This capability permits ADSI devices to communicate with users through a familiar voice response audio interface, where the user listens to voice recordings and makes menu selections using the telephone keypad, and with visual menus and information on a screen display, where service selections can be made using softkeys. Currently, ADSI devices are often implemented as screen-display telephone terminals, but there can also be television set-top boxes allowing users to make calls using the television, personal digital assistants (PDAs), pagers, and personal computers that are ADSI capable.
In addition to real-time interactive applications, ADSI also enables program transfer using a capability known as Feature Download. These programs, or service scripts, can be developed by a server and run on a local terminal. In many cases, these scripts are created by an authoring tool and stored in an external database for access by the telephony platform serving the user. Therefore, when new features are requested by the user, or are newly added by the server, the scripts are transferred by the telephony platform to the ADSI terminal where they are stored in memory and executed by the terminal until overwritten. These scripts define not only call flow, but also define the softkeys and displays presented to the user during a call.
One example of applied ADSI technology is Northern Telecom's Advanced Call Management Service (ACMS). In ACMS, customer selected features are stored in an external database. When a customer calls in for activation of services, a database lookup is performed so that the appropriate information for that customer can be downloaded to the telephone. The application runs on a Network Applications Vehicle (NAV), which is typically a UNIX-based telephony platform, and which reads an object file to get information concerning the call flow. The NAV presents the call flow, including ADSI commands, to the end user and as a result a new application is presented to the terminal.
In addition, any server may create Custom Local Area Signaling Services (CLASS).SM. or Custom Calling Features (CCF) and download these advanced feature download scripts that are specifically tailored to the user's service subscription. As a result, a user can activate services such as three-way calling, call waiting, and call forwarding through context sensitive screen prompts and softkeys. These advanced call management telephony script applications have been a primary area of development for ADSI display terminals.
An example of advanced ADSI script transfer is disclosed in U.S. Pat. No. 5,541,486, to Hou. Specifically, Hou discloses a method and system for automatically consolidating service scripts for downloading to ADSI-compatible screen-display telephones. The method and system comprises specifying a general template for a set of service features, specifying line specific attributes for a feature, and then combining the two into a service module. A customer's service is composed of multiple service modules which, when selected, would be consolidated by a network server computer into a single service script. Hou also discloses compiling the consolidated service script for downloading and transmission to a local processor in the compatible screen-display telephone.
2. The Internet
The Internet, or "net," fueled by the popularity of the World Wide Web (WWW or Web), has exhibited significant growth over the past few years. At present, to access the information available on the Web, users typically use standard computer equipment, such as a home personal computer with a display and modem, and an Internet connection.
There have been efforts to expand the number of users and the ease with which they access the net. For example, several companies have developed television set-top boxes that permit users to browse or "surf" the Internet from their television sets. In addition, telephone companies have joined with software developers to allow mobile communication devices such as cellular telephones, pagers, and PDAs to access some features of the Internet.
At present, several types of Internet connections are available. For example, to use an Internet connection from Internet Service Providers (ISPs), the user dials into a computer at the ISP's facility using a modem and standard telephone line. The ISP's computer in turn provides the user with access to the Internet. Through this Internet connection, the user can access information on the Web using a computer program called a "Web browser," such as for example the Netscape Navigator.TM. from Netscape Communications Corporation. The Web browser is a software program that allows a user to view the data received from an Internet site location. To accomplish this, the user gives the Web browser a Uniform Resource Locator (URL) for an object on the Internet, for example, a data file containing information of interest. The document is referred to as a "Web page," and the information contained in the Web page is called content. Web pages often refer to other Web pages using "hypertext link" or "hyperlinks" that include words or phrases representing the other pages in a form that gives the browser the URL for the corresponding Web page when a user selects a hyperlink.
Hyperlinks are made possible by building Web pages using a Hypertext Markup Language (HTML), an evolving language which is used to construct documents in a uniform, standardized format so they may be accessed by Web browsers and displayed for the user. HTML is an ASCII text-based language which defines page formats used to display the HTML elements. To ensure accessibility, all HTML documents have a "point-of-contact" name, or ANCHOR, identified in the document as part of the ANCHOR element. This name is hyperlink-enabled by surrounding the name with the &lt;A&gt; element. This feature permits a user to link with another URL when the ANCHOR element is selected.
Once the user selects a site to visit, the URL identifies a specific host computer on the Internet, called a "Web Server," and, more particularly, the location of a Web page located on the Web Server. The Web browser retrieves the Web page and displays it for the user. Hypertext Transfer Protocol (HTTP) is the most widely used format to access and link users with various other Web pages or sites referenced by the original Web page. HTTP requires a program running on the host computer that understands and responds to this protocol. The file retrieved might be, for example, an HTML file, a graphic file, a sound file, an animation sequence file, a file to be executed by the Web server (e.g., CGI programs), or a word processing file. Ultimately, whether the file can be retrieved or handled depends on the features and capabilities of the browser. When a browser requests a specific URL, it sends the request to the sponsoring Web server. The Web server receives the request and attempts to fulfill the request.
There are several ways that user requests can be fulfilled. For example, Web servers translate a request such as "http://www.recipes.com/recipes/soup.htm" into a search for a physical file on that server. It would start from the base directory for that domain and then apply the path that was requested. In this example, the Web server would look for a directory called "recipes" and then look for a file called "soup.htm" within that directory. If the file was found it would be passed back, without modification, to the requesting browser. In this way, the URL can be thought of as a specific file sitting on a server, or host computer.
Common Gateway Interface (CGI) was created as one way for Web servers to achieve a dynamic element by calling to programs that reside on the server. This dynamic element allows the Web server to immediately respond to the request without doing additional processing. The server receives a request from the browser, and it uses the dynamic element, or hypertext link, to connect with a new process. The server then passes CGI based tagged data that will be used by the program to create, for example, the HTML file. The CGI program executes the associated display format subroutine, or script file, and accesses other data sources to generate the content and then returns the HTML back to the HTTP server. Once the transfer is completed, the CGI process terminates and the server transfers the HTML back to the requesting browser.
An alternative to using separate CGI scripts to define content is a template-based HTML that actually embeds a request for the dynamic data within the HTML file itself. When specific page is requested, a pre-processor scans the file for proprietary tags that are then translated into final HTML based on the request. The final HTML is then passed back to the server and on to the browser for the user to view on their computer terminal. While the examples given have been explained in the context of HTML, both CGIs and templates may be created with any Standard Generalized Markup Language (SGML) based markup language, such as Handheld Device Markup language (HDML). HDML is a markup language designed and developed by AT&T and Unwired Planet, Inc. to allow handheld devices some access to the resources of the Internet. The specifics of the language are disclosed in "HDML Language Reference, Version 1.0," Unwired Planet, Inc., July 1996, and herein incorporated by reference.
While computer terminals and other devices that are configured to receive HTTP signals and HTML files may utilize the above methods to access and view the Internet data, the specific display standards for ADSI devices, as well as the display capabilities for ADSI and other screen-display telephones, allow only a limited view of HTTP transferred HTML files. In addition, ADSI display characteristics do not permit a user to take advantage of the hypertext features imbedded in most HTML data files.
While the capability of ADSI devices have been explored to provide users with more advanced consumer-based telephone services, ADSI devices have not previously been integrated successfully and effectively with the vast resources of the Internet. In addition to permitting ADSI devices to retrieve data files from the Internet, the proposed ADSI Internet interface would also provide users with the ability to "jump" between ADSI applications by giving applications an imbedded link to other ADSI applications. This benefit would be similar to the benefits of hyperlinks used in HTML and has not been effectively implemented for ADSI application. Therefore, a need exists for a system and method that would allow ADSI device s to access and retrieve data from the Internet as well as link ADSI applications.